Registration apparatus, verification apparatus, registration method, verification method and program

ABSTRACT

A registration apparatus includes: concealing means for concealing a part or whole of a verification area of an image generated by shooting a body part, the verification area being used for verification; production means for producing data for registration, the data representing a part or whole of a pattern of the verification area; display control means for controlling display means to display an image in which a part or whole of the verification area is concealed; and output switching means for outputting the image to the display control means or the production means.

CROSS REFERENCES TO RELATED APPLICATIONS

The present invention contains subject matter related to Japanese PatentApplication JP2006-305624 filed in the Japanese Patent Office on Nov.10, 2006, the entire contents of which being incorporated herein byreference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a registration apparatus, verificationapparatus, registration method, verification method and program, and ispreferably applied to biometric identification, for example.

2. Description of the Related Art

One of physical characteristics for biometric identification is a bloodvessel. An authentication apparatus for example takes a picture of aperson's finger and then extracts from the image data a blood vesselpattern. The authentication apparatus subsequently compares theextracted blood vessel pattern with a registered blood vessel pattern tocalculate a correlation value between the extracted pattern and theregistered pattern. When the correlation value is greater than or equalto a predetermined threshold, the authentication apparatus determinesthat he/she is legitimate.

That kind of authentication apparatus is often equipped with a guide fora finger to be placed appropriately on an image-pickup position (seeJpn. Pat. Laid-open Publication No. 2005-71118, for example).

However, it seems better for the authentication apparatus not to have aguide in terms of design flexibility. Therefore, the authenticationapparatus can be downsized.

Accordingly, there is an apparatus that replaces the guide with adisplay system, which displays a finger's image and a guide's imagealong with information regarding a distance between the finger's imageand the guide's image (see Jpn. Pat. Laid-open Publication No.2006-141589, for example).

SUMMARY OF THE INVENTION

However, since the above display system displays a blood vessel pattern,it can be easily stolen by someone else.

The present invention has been made in view of the above points and isintended to provide a registration apparatus, verification apparatus,registration method, verification method and program that prevent leaksof pattern data.

In one aspect of the present invention, a registration apparatusincludes: concealing means for concealing a part or whole of averification area of an image generated by shooting a body part, theverification area being used for verification; production means forproducing data for registration, the data representing a part or wholeof a pattern of the verification area; display control means forcontrolling display means to display an image in which a part or wholeof the verification area is concealed; and output switching means foroutputting the image to the display control means or the productionmeans.

In another aspect of the present invention, a verification apparatusincludes: concealing means for concealing a part or whole of averification area of an image generated by shooting a body part, theverification area being used for verification; comparison means forcomparing a part or whole of a pattern of the verification area with apart or whole of a pattern of a registered verification area; displaycontrol means for controlling display means to display an image in whicha part or whole of the verification area is concealed; and outputswitching means for outputting the image to the display control means orthe comparison means.

In another aspect of the present invention, a registration methodincludes: a first step of concealing a part or whole of a verificationarea of an image generated by shooting a body part, the verificationarea being used for verification; a second step of controlling displaymeans to display an image in which a part or whole of the verificationarea is concealed; and a third step of stopping displaying the image inwhich a part or whole of the verification area is concealed or stoppingupdating the image displayed, and producing data for registration, thedata representing a part or whole of a pattern of the verification area.

In another aspect of the present invention, a verification methodincludes: a first step of concealing a part or whole of a verificationarea of an image generated by shooting a body part, the verificationarea being used for verification; a second step of controlling displaymeans to display an image in which a part or whole of the verificationarea is concealed; and a third step of stopping displaying the image inwhich a part or whole of the verification area is concealed or stoppingupdating the image displayed, and comparing a part or whole of a patternof the verification area with a part or whole of a pattern of aregistered verification area.

In another aspect of the present invention, a program for causing acomputer to execute: a step of concealing a part or whole of averification area of an image generated by shooting a body part, theverification area being used for verification; a step of controllingdisplay means to display an image in which a part or whole of theverification area is concealed; and a step of stopping displaying theimage in which a part or whole of the verification area is concealed orstopping updating the image displayed, and producing data forregistration, the data representing a part or whole of a pattern of theverification area.

In another aspect of the present invention, a program for causing acomputer to execute: a step of concealing a part or whole of averification area of an image generated by shooting a body part, theverification area being used for verification; a step of controllingdisplay means to display an image in which a part or whole of theverification area is concealed; and a step of stopping displaying theimage in which a part or whole of the verification area is concealed orstopping updating the image displayed, and comparing a part or whole ofa pattern of the verification area with a part or whole of a pattern ofa registered verification area.

In that manner, they display a body part such that a part or whole ofthe verification area is concealed. This conceals the verification areawhile indicating the current position of a user's finger with respect tothe target position in real time. Thus, the registration apparatus, theverification apparatus, the registration method, the verification methodand the programs thereof can prevent leak of the pattern data of theverification area without being equipped with a physical guide section.

The nature, principle and utility of the invention will become moreapparent from the following detailed description when read inconjunction with the accompanying drawings in which like parts aredesignated by like reference numerals or characters.

BRIEF DESCRIPTION OF THE DRAWINGS

In the accompanying drawings:

FIG. 1 is a block diagram illustrating the configuration of anauthentication apparatus according to an embodiment of the presentinvention;

FIG. 2 is a flowchart illustrating a first registration process;

FIG. 3 is a schematic diagram illustrating setup of a mask area;

FIG. 4 is a schematic diagram illustrating a guide display screen (1);

FIG. 5 is a flowchart illustrating a first authentication process;

FIG. 6 is a schematic diagram illustrating a guide display screen (2);

FIG. 7 is a schematic diagram illustrating an example of templateimages;

FIGS. 8A to 8C are schematic diagrams illustrating fake blood vesselpatterns to be attached to a finger area;

FIG. 9 is a flowchart illustrating a second registration process;

FIGS. 10A and 10B are schematic diagrams illustrating an image shot whena near infrared ray or visible ray is used for shooting;

FIG. 11 is a schematic diagram illustrating a guide display screen (3);

FIG. 12 is a flowchart illustrating a second authentication process; and

FIG. 13 is a schematic diagram illustrating a guide display screen (4).

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

An embodiment of the present invention will be described in detail withreference to the accompanying drawings.

(1) Overall Configuration of an Authentication Apparatus

FIG. 1 illustrates the configuration of an authentication apparatus 1according to an embodiment of the present invention. The authenticationapparatus 1 includes a control section 10 connected to an operationsection 11, an image pickup section 12, a flash memory 13, a displaysection 14 and an audio output section 15 via a bus 16.

The control section 10 is for example a microcomputer including; aCentral Processing Unit (CPU), which takes overall control of theapparatus 1; a Read Only Memory (ROM), which stores various programs andsetting information; and a Random Access Memory (RAM), which serves as awork memory for the CPU.

When operated by a user, the operation section 11 supplies to thecontrol section 10 a command COM1, a command COM2 or the like: Thecommand COM1 orders the control section 10 to operate in blood vesselregistration mode for registering a user's blood vessel pattern whilethe command COM2 orders the control section 10 to operate inauthentication mode for verifying a user.

After receiving the command COM1 or COM2, the control section 10operates in the blood vessel registration mode or the authenticationmode. In this case, the control section 10 executes a correspondingprogram to control the image pickup section 12, the flash memory 13, thedisplay section 14 and the audio output section 15.

(1-1) Blood Vessel Registration Mode

When receiving the command for the blood vessel registration mode, thecontrol section 10 enters the blood vessel registration mode and thenstarts controlling the image pickup section 12.

A driver section 12 a of the image pickup section 12 turns on a nearinfrared ray source LS to emit a near infrared ray to a predeterminedimage pickup location. In addition, the drive section 12 a controls animage pickup element ID.

The drive section 12 a also adjusts the position of an optical lens, apart of the optical system OP, to focus on a subject. In addition, thedriver section 12 a adjusts an aperture DH based on an Exposure Value(EV) set by the control section 10. Moreover, the driver section 12 aadjusts a shutter speed (exposure time) for the image pickup element ID.

The authentication apparatus 1 is designed to pick up an image of afinger. After a finger is placed on the image pickup position, the nearinfrared ray source LS emits a near infrared ray toward the finger.After being reflected and scattered inside the finger, the near infraredray finally reaches the image pickup element ID, which receives it as ablood vessel reflection ray representing a blood vessel pattern of thefinger. The image pickup element ID photo-electrically converts theblood vessel reflection ray at predetermined intervals into imagesignals S1 i (i=1, 2, 3, . . . and m (m: integer)), which are thensupplied to the control section 10 via the driver section 12 a.

When receiving a registration start command from the operation section11, the control section 10 picks up, out of the image signals S1 i, animage signal S1 m supplied from the image element ID at this time. Thecontrol section 10 subsequently extracts from the image signal S1 m ablood vessel pattern image and then stores the extracted blood vesselpattern image in the flash memory 13 as registration image data D1.

In that manner, the control section 10 operates in the blood vesselregistration mode.

(1-2) Authentication Mode

When receiving the command for the authentication mode, the controlsection 10 enters the authentication mode and then starts controllingthe image pickup section 12.

In similar way to the blood vessel registration mode, the image pickupsection 12 adjusts the position of the optical lens of the opticalsystem OP, the aperture DH based on the EV set by the control section10, and the shutter speed for the image pickup element ID. Subsequently,the image pickup element ID supplies image signals S2 j (j=1, 2, 3, . .. and n (n: integer)) to the control section 10.

In the same way as the above blood vessel registration mode, the controlsection 10 extracts from the image signal S2 j a blood vessel patternimage and then compares it with the blood vessel pattern image of theregistration image data D1 registered in the flash memory 13.

If the control section 10 recognizes, before a predetermined period oftime has passed since start of the authentication mode, that acorrelation value between those blood vessel pattern images is greaterthan or equal to a predetermined threshold, the control section 10determines that the user is a legitimate registrant. In response tothat, the control section 10 performs a predetermined process for thelegitimate user and then ends the authentication mode.

Whereas if the control section 10 does not recognize, before thepredetermined period of time has passed, that a correlation valuebetween those blood vessel pattern images is greater than or equal to apredetermined threshold, the control section 10 determines that the useris not a legitimate registrant. In response to that, the control section10 performs a predetermined process for the non-registered user and thenends the authentication mode.

In that manner, the control section 10 operates in the authenticationmode.

(2) Process by the Control Section

Following describes the process of the control section 10. The controlsection 10 of the authentication apparatus 1 performs either a firsttype of process or a second type of process.

(2-1) First Type

Following describes a first type of process, which is performed by thecontrol section 10, including a registration process (for the bloodvessel registration mode) and an authentication process (for theauthentication mode).

(2-1-1) Registration Process

FIG. 2 is a flowchart illustrating a registration process (also referredto as a “first registration process”), which is performed by the controlsection 10 as the first type of process.

When receiving the blood vessel registration mode execution command COM1(FIG. 1), the control section 10 starts the first registration processand then proceeds to step SP1. At step SP1, the control section 10starts to control the image pickup section 12 (FIG. 1) and then proceedsto step SP2. At step SP2, the control section 10 performs a filteringprocess, such as Laplacian, to obtain an outline of a finger from theimage signals S1 i (FIG. 1) supplied from the image pickup section 12and then proceeds to step SP3.

At step SP3, the control section 10 masks an area inside the outline ofthe finger (also referred to as a “finger area”) to make the bloodvessels of the finger area substantially invisible.

For example, as shown in FIG. 3, the control section 10 detects a centerline extending along a longitudinal side of the finger outline and acenter line extending along a shorter side of the finger outline. Basedon these two center lines, the control section 10 puts a rectangularframe, whose center is a cross point of the two center lines, on thefinger image as a mask area AR.

Subsequently, the control section 10 divides the mask area AR into x×ypixel blocks. The control section 10 calculates the average of luminanceof each block and then applies it to each block so that the mask area ARbecomes a mosaic.

At subsequent step SP4, the control section 10 combines the masked imagedata with a template that indicates where a finger should be placed onan image pickup surface. The control section 10 displays a resultantguide display screen on the display section 14 (FIG. 1).

For example, the control section 10 displays on the display section 14(FIG. 1) a guide display screen including an finger area image FM1 i,which has a mask covering the blood vessel patterns, and a T-shapedguide mark image GM1, which indicates where the tip and center of afinger should be placed on the image pickup surface.

At subsequent step SP5, the control section 10 checks if it has receiveda registration start command from the operation section 11 (FIG. 1). Ifthe control section 10 has received the registration start command fromthe operation section 11, the control section 10 proceeds to step SP6.At step SP6, the control section 10 checks if the authenticationapparatus 1 is continuously taking a picture of the finger, byconfirming that it is still obtaining the finger outlines from the imagesignals S1 i, which have been supplied since it received theregistration start command.

If the control section 10 recognizes that it has not received theregistration start command or that it is not continuously taking apicture of the finger (even after receiving the registration startcommand), the control section 10 returns to step SP2 and retries theprocess.

In that manner, while continuously shooting the finger, the controlsection 10 keeps displaying the guide mark GM1 and the finger area imageFM1 i, which is updated each time an image of the finger is shot, untilit receives the registration start command. Accordingly, the guide markGM1 helps the finger to be placed appropriately at a predetermined imagepickup position while the finger area image FM1 i prevents people fromrecognizing the blood vessel patterns.

On the other hand, if the control section 10 recognizes that it hasreceived the registration start command and that it is continuouslyshooting the finger, the control section 10 proceeds to step SP7. Atstep SP7, the control section 10 changes its image processing mode froma mask processing mode, which is started at step SP3, to a blood vesselpattern extraction processing mode. At the same time, the controlsection 10 stops displaying the guide display screen or stops updatingthe finger area image FM1 i. At subsequent step SP8, the control section10 extracts a blood vessel pattern image from the image data of thefinger outline by performing a smoothing process, a binarization processand a thinning process and then proceeds to step SP9.

At step SP9, the control section 10 stores (registers) the blood vesselpattern image in the flash memory 13 (FIG. 1) as the registration imagedata D1 and then proceeds to step SP10. At step SP10, the controlsection 10 stops operating the image pickup section 12 (FIG. 1) to endthe first registration process.

In that manner, the control section 10 performs the first registrationprocess.

(2-1-2) Authentication Process

FIG. 5 is a flowchart illustrating an authentication process (alsoreferred to as a “first authentication process”), which is performed bythe control section 10 as the first type of process.

When receiving the authentication mode execution command COM2 (FIG. 1),the control section 10 starts the first authentication process andproceeds to step SP11. At step SP11, the control section 10 startsoperating the image pickup section 12 (FIG. 1) and then proceeds to stepSP12. The control section 10 at step SP12 starts measuring time to checkif a predetermined period of time for comparison (verification) haspassed. The control section 10 subsequently proceeds to step SP13.

At step SP13, the control section 10 extracts an outline of a fingerfrom the image signals S2 j (FIG. 1) supplied from the image pickupsection 12 by performing a predetermined filtering process. Atsubsequent step SP14, the control section 10 performs the maskingprocess and blood vessel pattern extraction process (which are the sameas the first registration process) for the extracted outline image.

At subsequent step SP15, the control section 10 combines the maskedimage data with the registration image data D1 (FIG. 1) registered inthe flash memory 13 (FIG. 1) to generate a guide display screen, whichis then displayed on the display section 14 (FIG. 1).

For example, as shown in FIG. 6, the control section 10 displays on thedisplay section 14 (FIG. 1) a guide display screen including a fingerarea image FM1 j, which has a mask covering the blood vessel pattern ofa target finger, and a guide mark GM2, which represents the outline of afinger to show the position of the finger when it was registered.

At subsequent step SP16, the control section 10 compares the image dataof the extracted blood vessel pattern (obtained at step SP14) with thatof the registration image data D1 (FIG. 1) registered in the flashmemory 13 (FIG. 1) and then proceeds to step SP17. The control section10 at step SP17 checks if a correlation value between those images isgreater than or equal to a predetermined threshold.

If the correlation value between those images is less than thethreshold, the control section 10 proceeds to step SP18 and then checksif the predetermined period of time for comparison has passed. If thatperiod has not passed yet, the control section 10 returns to step SP13and then retries the above process.

In that manner, the control section 10 keeps displaying the guide markGM2 and the finger area image FM1 j, which is updated each time an imageof the finger is shot, until the predetermined period of time forcomparison has passed. Accordingly, the guide mark GM2 helps the fingerto be placed appropriately at the same position as when the finger wasregistered, while the finger area image FM1 j prevents people fromrecognizing the blood vessel patterns.

If the control section 10 recognizes, before the predetermined period oftime for comparison has passed, that the correlation value between thoseimages is greater than or equal to the threshold, the control section 10determines that the user is legitimate. In this case, the controlsection 10 proceeds to step SP19 to perform a process for registeredlegitimate users: the control section 10 for example lifts restrictionon some operation modes, which were prohibited from being performed, andthen informs the user accordingly through the display section 14(FIG. 1) and the audio output section 15 (FIG. 1). The control section10 subsequently ends the authentication process.

Whereas if the control section 10 does not recognize, before thepredetermined period of time for comparison has passed, that thecorrelation value between those images is greater than or equal to thethreshold, the control section 10 determines that the user is notlegitimate. In this case, the control section 10 proceeds to step SP20to perform a process for non-registered users: the control section 10notifies the user of the fact that he/she is not a legitimate userregistered in the authentication apparatus 1 through the display section14 (FIG. 1) and the audio output section 15 (FIG. 1). The controlsection 10 subsequently ends the authentication process.

In that manner, the control section 10 performs the first authenticationprocess.

(2-1-3) Operation and Effect of the First-Type Process

Following describes the operation and effect regarding the first type ofprocess. The authentication apparatus 1 masks part of the finger image,which is to be registered, with a mosaic; this part of the finger imageincludes the blood vessel pattern.

When operating in the blood vessel registration mode, the authenticationapparatus 1 displays the T-shaped guide mark GM1 indicating where thetip and center of a finger should be placed and the finger area imageFM1 i including a mask covering the blood vessel pattern which is to beregistered (FIG. 4).

On the other hand, when operating in the authentication mode, theauthentication apparatus 1 displays the guide mark GM2 having afinger-outline shape for indicating the position of the finger when itwas shot for registration and the finger area image FM1 j including amask covering the blood vessel pattern which corresponds to the partregistered (FIG. 6).

In that manner, the authentication apparatus 1 conceals the blood vesselpatterns. In addition, the authentication apparatus 1 helps a userunderstand where he/she is putting his/her finger. The user canunderstand the current position of his/her finger with respect to thetarget. Accordingly, the authentication apparatus 1 does not have tohave a physical component for guiding fingers. In addition, theauthentication apparatus 1 prevents information regarding blood vesselpatterns from being leaked.

Moreover, the authentication apparatus 1 displays the T-shaped guidemark GM to help a user register his/her finger, the T-shaped guide markGM indicating where the tip and center of the finger should be placed.Accordingly, everyone can appropriately put their fingers although thelength and width of fingers differ for each individual. Theauthentication apparatus 1 also displays another guide mark GM forauthentication, this guide mark GM representing an outline of a fingerto indicate the image pickup position (where a finger should be placedfor authentication) that is the same as that of the registration mode.This helps a user to put his/her finger on the right position.

(2-1-4) Other Examples of the First-Type Process

In the above-noted first-type process, a concealing means performs amasking process to set the mosaic mask area AR (FIG. 3). However, thepresent invention is not limited to this. The apparatus may performanother masking process, such as transforming the mask area AR (FIG. 3)into a radial pattern or a stripe pattern, replacing a block withanother block, putting noise over the area AR, replacing the area imageAR with another image, or the like to make the mask area ARsubstantially invisible. The apparatus may perform several types ofmasking processes at once.

Moreover, in the above-noted first-type process, the center of thefinger is concealed as the mask area AR. However, the present inventionis not limited to this. Instead, the entire surface of the finger orother parts of the finger may be concealed.

Furthermore, instead of performing the masking process, the apparatusmay use images IM1 to IM9 (FIG. 7), which look like an outline of afinger on the image pickup surface, as templates: The apparatus maychoose one of the images IM1 to IM9 (pre-stored in the ROM or the like)whose outline is similar to the result of the outline extraction processand then combines it with another template or the registration imagedata D1. This helps reduce processing load regarding step SP4 (FIG. 2)of the blood vessel registration mode and step SP15 (FIG. 5) of theauthentication mode.

Furthermore, in the above-noted first-type process, the apparatus isdesigned to display the T-shaped guide mark GM1 to indicate where thetip and center of a finger should be placed. However, the presentinvention is not limited to this. The apparatus may displaydifferently-shaped guide marks. Alternatively, the apparatus may use atemplate having a guide mark and a background representing the actualcircumstance for a finger to be placed. This provides a user with arealistic feeling. Accordingly, the apparatus is easy-to-use.

Furthermore, in the above-noted first-type process, the apparatusdisplays on the display section 14 the guide display screen generated bycombining the masked image and the template (which is an imageindicating where a finger should be placed). However, the presentinvention is not limited to this. Alternatively, the apparatus maydisplay on the display section 14 the masked image as a guide displayscreen.

In that case, the center (image pickup position) of the masked image andthis image's finger area (i.e. the masked area AR of a body part) help auser understand the current position of his/her finger with respect tothe target position. In this manner, the apparatus can guide the user'sfinger.

By the way, if the apparatus is equipped with a physical guide sectionto indicate where a finger should be placed, the image shot by the imagepickup section 12 may show the guide section as well as a finger. Inthis case, after masking that image, the apparatus only displays thismasked image because it shows a body part (finger) whose blood vesselpattern has been concealed and the target position where a finger shouldbe placed. Accordingly, this method can present the same effect as theabove-noted first-type process.

Furthermore, in the above-noted first-type process, the apparatus isdesigned to display images to indicate the position where a fingershould be placed and the current position of the finger. In addition tothat, the apparatus may display an indicator to indicate whether thecondition for shooting is good or bad.

There is a possibility that a finger at a predetermined position of theauthentication apparatus 1 is too much illuminated for shooting due tothe conditions. In this case, the blood vessel pattern images shot maydiffer for the registration mode and the authentication mode even if thefinger was placed at the same position. Accordingly, displaying theindicator helps a user correct it himself/herself. Thus, the apparatusis easy-to-user.

Another method to solve the above problem is to equip the apparatus witha physical cover that covers around a finger at the image pickupposition and shuts off light from the outside. However, this increasesthe complexity of the apparatus. In addition, the apparatus cannot beeasily downsized. Accordingly, the indicator is more effective than thephysical cover.

Following describes an example of how the apparatus displays theindicator. After the outline extraction process (step SP2 (FIG. 2) orstep SP13 (FIG. 5)) to extract an outline of a finger, the controlsection 10 calculates values regarding the brightness (such asbrightness distribution and brightness average) of the finger area ofthe image representing the extracted outline.

The control section 10 subsequently checks which one of the followingranges the calculated values belong to: a first range, which is definedas a good shooting condition; a second range, which is defined as anot-so-good-but-not-so-bad shooting condition; and a third range, whichis defined as a bad shooting condition.

When it determines the shooting condition is bad, this means that thevariability of illumination for a finger is significant. In this case,as the variability of illumination increases, the brightnessdistribution will be leveled off while the brightness average willincrease.

When the calculated values are within the first range, the controlsection 10 at step SP3 or SP14 performs a strong masking process to makeit substantially invisible. When the calculated values are within thesecond range, the control section 10 at step SP3 or SP14 performs arelatively weaker masking process which still makes it substantiallyinvisible. When the calculated values are within the third range, thecontrol section 10 at step SP3 or SP14 performs a weaker masking processwhich allows a user to see it, or does not perform a masking process.

In this manner, the apparatus presents a strong mask or a weak mask asthe indicator. If a user does not recognize the effect of masking,he/she can estimate that the current condition is good for shooting.Whereas if a user recognizes the effect of masking, he/she can estimatethat the current condition is bad for shooting.

If the apparatus is designed to display the template images IM (FIG. 7)instead of masking, the control section 10 at step SP3 or SP14 attaches,when the calculated values are within the first range, a fake bloodvessel pattern image including many lines (FIG. 8A) to the image IMwhose outline is similar to the result of the outline extractionprocess. When the calculated values are within the second range, thecontrol section 10 attaches a fake blood vessel pattern image includingnot-so-many lines (FIG. 8B) to the image IM. When the calculated valuesare within the third range, the control section 10 attaches a fake bloodvessel pattern image including a few lines (FIG. 8C) to the image IM.

In that manner, the number of lines of the fake blood vessel patternimages represents whether the shooting condition is good or bad. Whenthere are many lines, a user may determine that the shooting conditionis good. When there are a few lines, a user may determine that theshooting condition is bad.

By the way, in the above case, the shooting condition is evaluated basedon the values of brightness inside the finger image. Alternatively, theshooting condition may be evaluated based on the number of blood vesselsin the image. On the other hand, the evaluation of the shootingcondition is expressed by the level of masking or by the number of linesof the fake blood vessel pattern images. Alternatively, the evaluationmay be expressed in a massage such as “The current condition forshooting is . . . ”

In that manner, the number of blood vessels inside the finger area ofthe image (which represents the extracted outline of the finger) issimply evaluated based on the values of brightness on a scale of 0 to n.And the authentication apparatus 1 displays the evaluation. Accordingly,a user can recognize the shooting condition in real time. That is, auser can recognize that the shooting condition sometimes may not be goodenough for shooting even if he/she put his/her finger appropriately, andtherefore could refrain from starting registration. Thus, theauthentication apparatus 1 is easy-to-use.

(2-2) Second Type

The following describes the second type of process. In the second typeof process, the authentication apparatus 1 uses a near infrared ray toshoot blood vessels. In this case, the blood vessel pattern is concealedby shooting a finger under the condition in which the apparatus stopsemitting the near infrared ray to the finger. This method is differentfrom that of the first-type process that masks the blood vessel pattern.A second-type registration process (blood vessel registration mode) andauthentication process (authentication mode) by the control section 10will be described in detail.

(2-2-1) Registration Process

FIG. 9 is a flowchart illustrating the second-type registration process(also referred to as a “second registration process”) by the controlsection 10.

When receiving the blood vessel registration mode execution command COM1(FIG. 1), the control section 10 starts the second registration processand then proceeds to step SP21. At step SP21, the control section 10starts driving the image pickup section 12 (FIG. 1) but the nearinfrared ray source LS (FIG. 1) is not started yet.

The near infrared rays are particularly absorbed by hemoglobin in theblood vessels. As a result of emitting the near infrared rays to afinger, the rays received by the image pickup section 12 represent thepattern of the blood vessels of the finger, and FIG. 10A is the imageshot by the image pickup section 12.

On the other hand, when not emitting the near infrared rays to a finger,the image pickup section 12 just receives visible rays representing thefinger, and FIG. 10B is the image shot by the image pickup section 12.In that manner, when the control section 10 is driving the image pickupsection 12 except the near infrared ray source LS (FIG. 1), the bloodvessel pattern area of the image shot by the image pickup section 12 isconcealed completely.

In a similar way to the above first registration process, the controlsection 10 at subsequent step SP22 extracts an outline of the fingerfrom the image shot. At subsequent step SP23, the control section 10displays on the display section 14 (FIG. 1) a guide display screenincluding a finger area FM2 i, which is surrounded by the outline, andthe T-shaped guide mark GM1, which indicates where the tip and center ofthe finger should be placed on the image pickup screen, as shown in FIG.11.

At subsequent step SP24, the control section 10 checks if it hasreceived from the operation section (FIG. 1) the registration startcommand. If the control section 10 has received the registration startcommand from the operation section 11, the control section 10 proceedsto step SP25. At step SP25, the control section 10 checks if theauthentication apparatus 1 is continuously shooting the finger, byconfirming that it is still obtaining the finger outlines from the imagesignals S1 i, which have been supplied since it received theregistration start command.

If the control section 10 recognizes that it has not received theregistration start command or that it is not continuously shooting thefinger (even after receiving the registration start command), thecontrol section 10 returns to step SP22 and retries the process.

In that manner, while continuously shooting the finger, the controlsection 10 keeps displaying the guide mark GM1 and the finger area imageFM2 i, which is updated each time an image of the finger is shot, untilit receives the registration start command. Accordingly, the guide markGM1 helps the finger to be placed appropriately at a predetermined imagepickup position while the finger area image FM2 i prevents people fromrecognizing the blood vessel patterns.

On the other hand, if the control section 10 recognizes that it hasreceived the registration start command, the control section 10 proceedsto step SP26 and starts driving the near infrared ray source LS to takea picture of the blood vessels of the finger. In addition, the controlsection 10 stops displaying the guide display screen or stops updatingthe finger area image FM2 i on the guide display screen, and thenproceeds to step SP27.

At step SP27, the control section 10 extracts the blood vessel patternfrom the image data representing the extracted outline of the finger, byfor example performing a smoothing process, a binarization process and athinning process, and then proceeds to step SP28.

At step SP28, the control section 10 stores (or registers) the bloodvessel pattern image in the flash memory 13 (FIG. 1) as the registrationimage data D1 and then proceeds to step SP29. At step SP29, the controlsection 10 stops the image pickup section 12 (FIG. 1) to end the secondregistration process.

In that manner, the control section 10 performs the second registrationprocess.

(2-2-2) Authentication Process

FIG. 12 is a flowchart illustrating the second-type authenticationprocess (also referred to as a “second authentication process) by thecontrol section 10.

When receiving the authentication mode execution command COM2 (FIG. 1),the control section 10 starts the second authentication process. In asimilar way to the above second registration process, the controlsection 10 at subsequent step SP31 starts driving the image pickupsection 12 (FIG. 1), but the near infrared ray source LS (FIG. 1) is notstarted yet. At subsequent step SP32, the control section 10 extracts anoutline of a finger from an image shot by the image pickup section 12and then proceeds to step SP33. At step SP33, the control section 10displays on the display section 14 (FIG. 1) a guide display screenincluding a finger area FM2 j, which is surrounded by the finger'soutline, and the guide mark GM2, which represents the outline of thefinger to indicate the image pickup position where the finger was onceplaced for registration, as shown in FIG. 13.

At subsequent step SP34, the control section 10 checks if it hasreceived a verification start command from the operation section (FIG.1). If the control section 10 has received the verification startcommand from the operation section 11, the control section 10 proceedsto step SP35. At step SP35, the control section 10 checks if theauthentication apparatus 1 is continuously shooting the finger, byconfirming that it is still obtaining the finger outlines from the imagesignals S21, which have been supplied since it received the verificationstart command.

If the control section 10 recognizes that it has not received theverification start command or that it is not continuously shooting thefinger (even after receiving the verification start command), thecontrol section 10 returns to step SP32 and retries the process.

In that manner, while continuously shooting the finger, the controlsection 10 does not start the verification process until it receives theverification start command. Instead the control section 10 keepsdisplaying the guide mark GM2 and the finger area image FM2 j, which isupdated each time an image of the finger is shot. Accordingly, the guidemark GM2 helps the finger to be placed appropriately at a predeterminedimage pickup position while the finger area image FM2 j prevents peoplefrom recognizing the blood vessel patterns.

On the other hand, if the control section 10 recognizes that it hasreceived the verification start command, the control section 10 proceedsto step SP36 and starts driving the near infrared ray source LS to takea picture of the blood vessels of the finger. At subsequent step SP37,the control section 10 starts measuring time to check if a predeterminedperiod of time for comparison (verification) has passed. The controlsection 10 subsequently proceeds to step SP38.

At step SP38, the control section 10 extracts a blood vessel pattern ofthe finger from the image signals S2 j (FIG. 1) supplied from the imagepickup section 12 by for example performing a smoothing process, abinarization process and a thinning process. At subsequent step SP39,the control section 10 compares the extracted blood vessel pattern withthat of the registration image data D1 (FIG. 1) registered in the flashmemory 13 (FIG. 1). At subsequent step SP40, the control section 10checks if a correlation value between those images is greater than orequal to a predetermined threshold.

If the correlation value between those images is less than thethreshold, the control section 10 proceeds to step SP41 and then checksif the predetermined period of time for comparison has passed. If thatperiod has not passed yet, the control section 10 returns to step SP38and then repeats the above process until that period has passed.

If the control section 10 recognizes, before the predetermined period oftime for comparison has passed, that the correlation value between thoseimages is greater than or equal to the threshold, the control section 10determines that the user is legitimate. In this case, the controlsection 10 proceeds to step SP42 to perform a process for registeredlegitimate users: the control section 10 for example lifts restrictionon some operation modes, which were prohibited from being performed, andthen informs the user accordingly through the display section 14(FIG. 1) and the audio output section 15 (FIG. 1). The control section10 subsequently ends the authentication process.

Whereas if the control section 10 does not recognize, before thepredetermined period of time for comparison has passed, that thecorrelation value between those images is greater than or equal to thethreshold, the control section 10 determines that the user is notlegitimate. In this case, the control section 10 proceeds to step SP43to perform a process for non-registered users: the control section 10notifies the user of the fact that he/she is not a legitimate userregistered in the authentication apparatus 1 through the display section14 (FIG. 1) and the audio output section 15 (FIG. 1). The controlsection 10 subsequently ends the authentication process.

In that manner, the control section 10 performs the secondauthentication process.

(2-2-3) Operation and Effect of the Second-Type Process

Following describes the operation and effect regarding the second typeof process. The authentication apparatus 1 starts driving the imagepickup section 12 (FIG. 1) except the near infrared ray source LS (FIG.1). The authentication apparatus 1 does not start the near infrared raysource LS until it receives the registration or verification startcommand from the operation section 11 (FIG. 1).

When operating in the blood vessel registration mode, the authenticationapparatus 1 turns off the near infrared ray source LS to conceal theblood vessel pattern of the finger area FM2 i of the image shot. Theauthentication apparatus 1 displays this image and the T-shaped guidemark GM1 indicating where the tip and center of a finger should beplaced, which are updated each time an image of the finger is shot (FIG.9).

When operating in the authentication mode, the authentication apparatus1 turns off the near infrared ray source LS to conceal the blood vesselpattern of the finger area FM2 i of the image shot. The authenticationapparatus 1 displays this image and the guide mark GM2 representing theoutline of the finger to indicate the image pickup position where thefinger was once placed for registration, which are updated each time animage of the finger is shot (FIG. 11).

The authentication apparatus 1 therefore conceal the blood vesselpatterns in a similar way to the first-type process. In addition, a usercan recognize the position of his/her finger with respect to the targetposition in real time.

Moreover, the second-type process does not perform an image processingprocess (masking process) while the first registration process does.This reduces processing load. Furthermore, the second-type process isdesigned to turn off the near infrared ray source LS. The authenticationapparatus 1 therefore consumes lower amounts of power.

(2-2-4) Other Examples of the Second-Type Process

In the above-noted second-type process, the apparatus is designed todisplay the T-shaped guide mark GM1 to indicate where the tip and centerof a finger should be placed. However the present invention is notlimited to this. The apparatus may display differently-shaped guidemarks. Alternatively, the apparatus may use a template having a guidemark and a background representing the actual circumstance for a fingerto be placed. This provides a user with a realistic feeling.Accordingly, the apparatus is easy-to-use.

Moreover, in the above-noted second-type process, the guide displayscreen, displayed on the display section 14, is generated by combiningthe image, whose blood vessel pattern of the finger area FM2 i has beenconcealed as a result of turning off the near infrared ray source LS,and the template image, which indicates where the tip and center of afinger should be placed. However, the present invention is not limitedto this. In a similar way to the first-type process, the guide displayscreen, displayed on the display section 14, may only include the imagewhose blood vessel pattern of the finger area FM2 i has been concealed.

Furthermore, in the above-noted second-type process, the apparatus isdesigned to display images to indicate the position where a fingershould be placed and the current position of the finger. In addition tothat, the apparatus may display an indicator to indicate whether thecondition for shooting is good or bad, in a similar way to thefirst-type process.

Following describes an example of how the apparatus displays theindicator. After the outline extraction process (step SP22 (FIG. 9) orstep SP32 (FIG. 12)) to extract an outline of a finger, the controlsection 10 calculates values regarding the brightness (such asbrightness distribution and brightness average) of the finger area ofthe image representing the extracted outline. The control section 10subsequently checks which one of the following ranges the calculatedvalues belong to: the first range, the second range and the third range.

When the calculated values are within the first range, the controlsection 10 at step SP23 or SP33 attaches a fake blood vessel patternimage including many lines (FIG. 8A) to the image. When the calculatedvalues are within the second range, the control section 10 attaches afake blood vessel pattern image including not-so-many lines (FIG. 8B) tothe image. When the calculated values are within the third range, thecontrol section 10 attaches a fake blood vessel pattern image includinga few lines (FIG. 8C) to the image.

By the way, in the above case, the shooting condition is evaluated basedon the values of brightness inside the finger image. Alternatively, theshooting condition may be evaluated based on the number of blood vesselsin the image. On the other hand, the evaluation of the shootingcondition is expressed by the level of masking or by the number of linesof the fake blood vessel pattern images. Alternatively, the evaluationmay be expressed in a massage such as “The current condition forshooting is . . . ”.

In that manner, the number of blood vessels inside the finger area ofthe image (which represents the extracted outline of the finger) issimply evaluated based on the values of brightness on a scale of 0 to n.And the authentication apparatus 1 displays the evaluation. Accordingly,a user can recognize the shooting condition in real time. That is, auser can recognize that the shooting condition sometimes may not be goodenough for shooting even if he/she put his/her finger appropriately, andtherefore could refrain from starting registration. Thus, theauthentication apparatus 1 is easy-to-use.

(3) Other Embodiments

In the above-noted embodiment, a biometric trait to be verified is ablood vessel pattern. However, the present invention is not limited tothis. Biometric traits for verification may include other physiologicaltrait patterns, such as fingerprints, mouth's pattern (wrinkles), nervefibers or the like. By the way, in the above-noted embodiment, the bloodvessel pattern is extracted from an image of fingers. However, thepresent invention is not limited to this. The blood vessel pattern maybe extracted from an image of palms, arms or the like.

Moreover, in the above-noted embodiment, the control section 10 readsout a program from the ROM and then loads it onto the RAM to execute it.The control section 10 therefore operates in the blood vesselregistration mode and the authentication mode. However, the presentinvention is not limited to this. The program may be installed from astorage medium, such as Compact Disc (CD), Digital Versatile Disc (DVD)and semiconductor memories, or may be acquired via the Internet.

Furthermore, in the above-noted embodiment, the control section 10performs the registration and authentication processes. However, thepresent invention is not limited to this. A graphics work station mayperform part of the process.

Furthermore, in the above-noted embodiment, there is the authenticationapparatus 1 that includes the image pickup function, the verificationfunction and the registration function. However, the present inventionis not limited to this. There may be a plurality of apparatus, each ofwhich includes a different one of the above functions.

The above method can be applied to biometrics verification.

It should be understood by those skilled in the art that variousmodifications, combinations, sub-combinations and alterations may occurdepending on design requirements and other factors insofar as they arewithin the scope of the appended claims or the equivalents thereof.

What is claimed is:
 1. A registration apparatus comprising: a centralprocessing unit (CPU); a concealing unit, performed by the CPU,concealing a part or whole of a verification area of an image generatedby shooting a body part, the verification area being used forverification; a production unit, performed by the CPU, producing datafor registration, the data representing a part or whole of a pattern ofthe verification area; a display control unit, performed by the CPU,controlling a display means to display the image in which the part orwhole of the verification area is concealed; and an output switchingunit, performed by the CPU, outputting the image to the display controlunit or the production unit, wherein the image is a first image, and thedisplay control unit controls the display means to display a secondimage generated by combining the first image in which a part or whole ofthe verification area is concealed, position data indicating where thebody part should be placed on an image pickup surface, and a backgroundimage representing an actual circumstance for the body part to beplaced.
 2. The registration apparatus of claim 1, wherein: theconcealing unit includes: an outline extraction section extracting anoutline of the body part from the image generated by shooting the bodypart; and an image processing section masking a part or whole of an areawithin the outline to make the part or whole of the area substantiallyinvisible.
 3. The registration apparatus of claim 2, further comprising:an evaluation unit evaluating a shooting condition according to abrightness state of the area or a number of objects in the verificationarea, wherein the image processing section masks the part or whole ofthe area to make the part or whole of the area substantially invisibleif the evaluation unit determines that the brightness state of the areais lower than a predetermined level, or the image processing sectionmasks the part or whole of the area in a way that the part or whole ofthe area is visible if the evaluation unit determines that thebrightness state of the area is greater than a predetermined level. 4.The registration apparatus according to claim 1, wherein: the concealingunit conceals the part or whole of a verification area of the imagegenerated by shooting the body part by controlling the stopping andstarting of a near infrared ray source directed at the body part,wherein the near infrared ray source is configured to generate at leasta portion of the image.
 5. A registration apparatus comprising: acentral processing unit (CPU); a concealing unit, performed by the CPU,concealing a part or whole of a verification area of an image generatedby shooting a body part, the verification area being used forverification, wherein the concealing unit includes: an outlineextraction section for extracting an outline of the body part from theimage generated by shooting the body part; and an image processingsection masking a part or whole of an area within the outline to makethe part or whole of the area substantially invisible; a productionunit, performed by the CPU, producing data for registration, the datarepresenting a part or whole of a pattern of the verification area; adisplay control unit, performed by the CPU, controlling a display meansto display the image in which the part or whole of the verification areais concealed; an output switching unit, performed by the CPU, outputtingthe image of the display control unit or the production unit; and anevaluation unit for evaluating a shooting condition according to abrightness state of the area or a number of objects in the verificationarea, wherein the image processing section masks the part or whole ofthe area to make the part or whole of the area substantially invisibleif the evaluation unit determines that the brightness state of the areais lower than a predetermined level, or the image processing sectionmasks the part or whole of the area in a way that the part or whole ofthe area is visible if the evaluation unit determines that thebrightness state of the area is greater than a predetermined level. 6.The registration apparatus according to claim 5, wherein: the image is afirst image; and the display control unit controls the display means todisplay a second image generated by combining the first image in which apart or whole of the verification area is concealed and position dataindicating where the body part should be placed on an image pickupsurface.
 7. The registration apparatus according to claim 5, wherein:the image is a first image; and the display control unit controls thedisplay means to display a second image generated by combining the firstimage in which a part or whole of the verification area is concealed,position data indicating where the body part should be placed on animage pickup surface, and a background image representing an actualcircumstance for the body part to be placed.